The following bar graph shows the sales of books (in thousands) from 3 branches of a company in three consecutive years 2018, 2019 and 2020.
What is the ratio of the total sales of branch A for the year 2018 to the total sales of branch C for the year 2020?

A

1 : 1

B

5 : 1

C

4 : 3

D

1 : 5